The present invention relates to a scaleable modular antenna array that uses standard subarrays and circuit assemblies.
Satellite communications have become an important component in worldwide telecommunications. As the demand for satellite communications increases, the need for communications satellites that are less expensive and quicker to develop also increases. One approach to providing such communications satellites is described in U.S. Pat. No. 5,666,128 to Murray et al., which describes an array antenna especially adapted for spacecraft use that includes a support frame made up of intersecting beams which form an xe2x80x9ceggcratexe2x80x9d of square openings and a plurality of subarrays or radiating tiles that are dimensioned to fit within the openings. There are limitations to this approach as applied to millimeter wave frequencies. One limitation is that the gaps between the radiating tiles become too large, in wavelengths at the frequency of interest, to achieve acceptable beam quality. The gaps between tiles are required to provide space for the support frame. Another limitation is based on the fact that, for a given coverage area, the quantity of phase shifters per radiating tile per radiated or received beam is proportional to the square of the frequency. At millimeter wave frequencies (xcx9c30 GHz), there is inadequate space in a tile to package the components required to create the number of radiated or received beams that are desired in many applications.
What is needed is a phased array antenna design that is modular and scaleable in terms of beam quantity, coverage area, and receive sensitivity/transmit effective isotropic radiated power (EIRP), which permits the design to be tailored to specific applications relatively inexpensively, quickly, and with low development risk.
The present invention is a phased array antenna design that is modular and scaleable in terms of beam quantity, coverage area, and receive sensitivity/transmit EIRP, which permits the design to be tailored to specific applications relatively inexpensively, quickly, and with low development risk. This invention can be applied to both transmit and receive phased array antenna applications.
In one embodiment of the present invention, a modular array building block for an antenna array comprises: a plurality of antenna elements, each antenna element operable to receive and output an electromagnetic wave signal, the antenna elements arranged adjacent to each other, a plurality of antenna element interface assemblies; each antenna element interface assembly coupled to one of the plurality of antenna elements and coupling the received signal to an amplifier, and a plurality of circuit board assemblies, the circuit board assemblies arranged substantially parallel to each other, each circuit board assembly comprising: a plurality of amplifiers, each amplifier operable to amplify a received signal from an antenna element, and a plurality of beamformers, each beamformer coupled to an output of an amplifier, wherein the circuit board assemblies, antenna element interface assemblies and antenna elements are arranged so as to form a module.
In one aspect of the present invention, the antenna elements are arranged adjacent to each other so as to form a grid pattern, such as a triangular grid pattern or a rectangular grid pattern.
In one aspect of the present invention, at least some of the circuit boards are populated with fewer amplifiers and beamformers than could be accommodated.
In one aspect of the present invention, the antenna elements are arranged so as to form a plurality of rows and the antenna elements and antenna element interfaces are oriented oppositely in adjacent rows. The circuit boards may have non-uniform spacing within the module. The antenna element interface assemblies may comprise waveguide assemblies.
In one aspect of the present invention, the antenna elements are arranged so as to form a plurality of rows and the antennas and antenna element interface assemblies are oriented similarly in adjacent rows. The circuit boards may have uniform spacing within the module. The antenna element interface assemblies may comprise waveguide assemblies.
In one aspect of the present invention, each antenna element interface assembly comprises a waveguide assembly. Each waveguide assembly may further comprise a waveguide filter. Each waveguide assembly further may comprise a signal probe operable to convert an electromagnetic wave signal from the antenna to a corresponding electrical signal and output the electrical signal to the amplifier.
In one aspect of the present invention, the module comprises larger antenna elements and a correspondingly smaller number of circuit board assemblies, larger antenna elements and correspondingly less populated circuit board assemblies, larger antenna elements and a correspondingly smaller number of less populated circuit board assemblies, smaller antenna elements and a correspondingly larger number of circuit board assemblies, smaller antenna elements and correspondingly more populated circuit board assemblies, or smaller antenna elements and a correspondingly larger number of more populated circuit board assemblies.
In one aspect of the present invention, the beamformers are radio frequency beamformers.
In one aspect of the present invention, the beamformers are intermediate frequency beamformers.
In one aspect of the present invention, connections between the plurality of amplifiers and the plurality of beamformers are interleaved so that if a number of amplifiers are omitted from a circuit board assembly, at least one beamformer can be omitted from the circuit board assembly
In one embodiment of the present invention, a modular array building block for an antenna array comprises: a plurality of antenna elements, each antenna element operable to transmit an electromagnetic wave signal, the antenna elements arranged adjacent to each other, a plurality of antenna element interface assemblies; each antenna element interface assembly coupled to one of the plurality of antenna elements and coupling the signal from an amplifier, and a plurality of circuit board assemblies, the circuit board assemblies arranged substantially parallel to each other, each circuit board assembly comprising: a plurality of amplifiers, each amplifier operable to amplify a signal coupled to an antenna element, and a plurality of beamformers, each beamformer coupled to an input to an amplifier, wherein the circuit board assemblies, antenna element interface assemblies and antenna elements are arranged so as to form a module.
In one embodiment of the present invention, an antenna array comprises: a plurality of antenna array modules interlocking so as to form a contiguous antenna array structure, wherein each antenna array module comprises: a plurality of antenna elements, each antenna element operable to receive and output an electromagnetic wave signal, the antenna elements arranged adjacent to each other, a plurality of antenna element interface assemblies; each antenna element interface assembly coupled to one of the plurality of antennas and coupling the received signal to an amplifier; and a plurality of circuit board assemblies, the circuit board assemblies arranged substantially parallel to each other, each circuit board assembly comprising: a plurality of amplifiers, each amplifier operable to amplify a received signal from an antenna element, and a plurality of beamformers, each beamformer coupled to an output of an amplifier, wherein the circuit board assemblies, antenna element interface assemblies and antenna elements are arranged so as to form a module. Signal frequency, control, and DC power harnesses are used to electrically connect the antenna array modules to form an antenna array. The signal frequency selected for beamforming and power combining may either be the radio frequency (RF) or an intermediate frequency (IF) frequency.
In one embodiment of the present invention, an antenna array comprises: a plurality of antenna array modules interlocking so as to form a contiguous antenna array structure, wherein each antenna array module comprises: a plurality of antenna elements, each antenna element operable to transmit an electromagnetic wave signal, the antenna elements arranged adjacent to each other, a plurality of antenna element interface assemblies; each antenna element interface assembly coupled to one of the plurality of antennas and coupling the signal from an amplifier, and a plurality of circuit board assemblies, the circuit board assemblies arranged substantially parallel to each other, each circuit board assembly comprising: a plurality of amplifiers, each amplifier operable to amplify a signal coupled to an antenna element, and a plurality of beamformers, each beamformer coupled to an input to an amplifier, wherein the circuit board assemblies, antenna element interface assemblies and antenna elements are arranged so as to form a module. Signal frequency, control, and DC power harnesses are used to electrically connect the antenna array modules to form an antenna array. The signal frequency selected for beamforming and power dividing may either be the RF frequency or an IF frequency.
In one embodiment of the present invention, an antenna array comprises: a plurality of antenna array modules interlocking so as to form a contiguous antenna array structure, wherein each antenna array module comprises: a plurality of antenna elements, each antenna element operable to receive and output an electromagnetic wave signal and to transmit an electromagnetic wave signal, the antenna elements arranged adjacent to each other; a plurality of antenna element interface assemblies, each antenna element interface assembly coupled to one of the plurality of antenna elements and coupling the received signal to a receive amplifier and coupling the signal to be transmitted from a transmit amplifier; and a plurality of circuit board assemblies, the circuit board assemblies arranged substantially parallel to each other, each circuit board assembly comprising: a plurality of receive amplifiers, each receive amplifier operable to amplify a received signal from an antenna element, a plurality of transmit amplifiers, each amplifier operable to amplify a signal coupled to an antenna element, a plurality of beamformers, each beamformer coupled to an input to a transmit amplifier and coupled to an output of a receive amplifier, a plurality of duplexing devices coupling a transmit amplifier output and a receive amplifier input to an antenna element interface assembly, a plurality of duplexing devices coupling each beamformer to a transmit amplifier input and to a receive amplifier output; wherein the circuit board assemblies, antenna element interface assemblies and antenna elements are arranged so as to form a module; and signal frequency, control, and DC power harnesses to electrically connect the plurality of antenna array modules so as to form the antenna array. The signal frequency selected for beamforming and power dividing/combining may either be the RF frequency or an IF frequency.